Anselmi from the Elektron-Users forums shared some detailed info on the Elektron Analog Four waveforms.
Since day 1 I found the eA4 very different sounding to other analog synths I own and owned
With wide open filters the oscillators got a very characteristic flavor that vary from octave to octave
I specially found the saw wave got thinner and “grainy” at the lower range, and the triangle became somewhat “saturated”
This characteristic sound (kinda “nasal”) could be taken as a good thing if you like it, but some users could miss a more “rounded” sound, similar to the classic analog synths we all know and love like a Roland SH or a Moog one.
So I attached a scope program to see if there is some evidence that support what I hear and also see if I can get close to the round bass tones of this classic synths
This is what I found when looking at the saw wave:
Downward octaves are represented by the number in each picture
A the left of the white line you can see a series of waveforms that not just change their period according with the played octave but also they change their shape
From 1 to 5 you can see how the initially more symmetrical saw change into a spike-like one, making it sound more thin at the lower octaves
Curiously, in octaves 6 the saw splits into 2 peaks that become very separated in octave 7…this adds even more “grain” and less “cream” to the bass end of this waveform
At the right of the white line you can see a direct comparison between the shapes of octave 2 and 5. I stretched octave 2’s waveform to fit the wavelength of octave 5 in order to make them the same pitch and just see the change in shape. Beyond the picture’s line distortion when stretching it, it’s evident that the waveform shrinks to the left, making it more asymmetrical and spike-like, thus thinner sounding
As weird as it could be the MnM’s saw wave (in the supersaw machine) is very similar in shape as you can see at the top of this column in green
Last column shows a little trick that I found to make the A4 saw more symmetrical and full-sounded in the low register: at the top you can see the saw in octave 4, below it you got the same but with filter overdrive = 20…you can see how the wave is becoming thicker (and you can hear it for sure) and at the lower figure you can see a much more classic saw wave when you rise filter 1 resonance to 74 and lower the overdrive to 12, with the cutoff wide open
Then you can use the LP mode of filter 2 to classic filtering…OK, you lost 1 filter but anyway most classic monosynths just got a lonely LPF.
Try this new “oscillator” sound and you can get much closer to an old roland synth…you can add the sub oscillator to make it fuller sounding.
BTW, in this kind of sounds when you’ re looking for just one oscillator and one square sub (typical Roland stuff) it’s better to set your wave in, say, oscillator 1 and then use oscillator 2 for the square sub oscillator (with no main wave in this one) so this way you can set the sub oscillator’s level
Now for the triangle wave, you got a similar behavior in the fact that the waveshape change with the octaves
At the higher ones (1) it’s a triangle but the low octaves shows a heavy distortion of the shape, like as a kind of “windowing” is happening. I found this is kinda nice sounding though and also that if you rise the pwm parameter to 25 you can get another saw-like waveform that increase the sonic palette of the A4